CZ301651B6 - Herbicidal mixture containing a 3-heterocyclyl-substituted benzoyl derivative and an adjuvant - Google Patents

Abstract

In the present invention, there is disclosed a herbicidal mixture, comprising a) 0.5 to 90 percent by weight of 3-heterocyclyl-substituted benzoyl derivative of the general formula I where: Re1 represents chlorine, or methyl, Re2 denotes methylsulfonyl, Re3 represents hydrogen, X denotes 4,5-dihydroisoxazolyl, Re4 represents a pyrazole of the general formula II, which is attached in the 4-position, Re5 denotes hydrogen, Re6 represents methyl, or an environmentally compatible salt thereof; b) 10 to 99.5 percent by weight of an adjuvant comprising i) a carboxylic acid alkyl ester group containing 1 to 5 carbon atoms in the alkyl moiety and the carboxylic acid having 5 to 22 carbon atoms, ii) a carboxylic acid containing 10 to 20 carbon atoms, iii) a partial phosphoric ester or a partial sulfuric ester of a monohydroxy-functional polyalkyl ether and iv) optionally an alkyl polyoxyalkylene polyether, wherein the compound of the general formula I and the adjuvant are present in synergistically effective amounts.

Description

Technical field

The present invention relates to a herbicidal mixture of a 3-heterocyclyl-substituted benzoyl derivative and an adjuvant having synergistic action. 3-Heterocyclyl-substituted benzoyl derivatives are known and are described, for example, in WO 96/26206, WO 97/41116, WO 97/41117 and WO 97/41118.

BACKGROUND OF THE INVENTION

EP-B-0584 227 discloses herbicidal compositions comprising substituted cyclohexanediones 15 and nitrogen fertilizers.

German patent application WO 99/63823 discloses herbicidal mixtures based on 3-heterocyclyl-substituted benzoyl derivatives and a nitrogen-based fertilizer and adjuvant.

SUMMARY OF THE INVENTION

The present invention relates to a herbicidal composition comprising 3-heterocyclyl-substituted benzoyl derivatives whose herbicidal activity is higher than that of the pure active compound. This object is achieved by a herbicidal mixture comprising

a) 0.5 to 90 wt. 3-heterocyclyl-substituted benzoyl derivative of the general formula I

in which

R ¹ is chloro, methyl;

R ² is methylsulfonyl-1;

R ³ is hydrogen;

X is 4,5-dihydroisoxazolyl;

R ⁴ is the pyrazole bonded at the 4-position of formula III

R ⁵

in which

R ⁵ is hydrogen;

R ⁶ is methyl;

or an environmentally acceptable salt thereof;

b) 10 to 99.5 wt. an adjuvant comprising i) a C 1 -C 5 -alkyl ester of a carboxylic acid containing 5 to 22 carbon atoms, ii) a C 10 -C 20 -carboxylic acid, iii) a partial phosphoric ester or a partial sulfur ester of a monohydrofunctional polyalkyl ether, iv) optionally alkyl polyoxyalkylene polyether 15 in a synergistically effective amount.

The herbicidal composition of the present invention exhibits a synergistic effect and is selective for those useful plants that are also compatible with the individual compounds.

Preferred compounds of Formula 1B are shown in the following table:

Έ- R ¹ T- R ³ R ⁵ R * X 2. Cl SO ₂ CH ₃ H H ch ₃ 2-thiazolyl 5. Cl SOjCHj H H CH ₃ 4,5-dihydroisoxazol-3-yl 6. Cl SOíCHj H H ch ₃ 4,5-dihydro-5-methylisoxazole- 3-yl 7, Cl SOjCH ₃ H H ch ₃ 4,5-dihydro-5,5- dimethylisoxazol-3-yl 8. Cl SO ₂ CH ₃ H H ch ₃ 4,5-Dihydro-5-ethylisoxazole-3- yi 9, Cl Sat ₂ ch ₃ H H ch ₃ 4,5-dihydro-5,5- diethylisoxazol-3-yl 10. Cl Sat ₂ ch ₃ H H ch ₃ 4,5-Dihydro-5- chloromethylisoxazol-3-yl 12, Cl SOjCH ₃ H H ch ₃ 4,5-dihydro-5-ethoxyisoxazole- 3-yl 13. Cl SO ₂ CH ₃ H H ch ₃ 4, S-dihydro-S-methoxyisoxazole- 3-yl 14. CH ₃ SOjCH ₃ H H ch ₃ 4,5-dihydroisoxazol-3-yl 15 Dec Cl Sat ₂ ch ₃ H H CH ₃ 4,5-dihydro-4,5- dimethylisoxazol-3-yl 16. Cl Sat ₂ ch ₃ H H CHj 4,5-Dihydro-5- thioethylisoxazol-3-yl 17. Cl Sat ₂ ch ₃ H H čh ₃ 4,5-Dihydro-5- trifluoromethylisoxazol-3-yl

-2GB 301651 B6

34. Cl SO ₂ CH ₃ H H ch ₃ 3-Methylisoxazol-5-yl 39. CH ₃ Sat ₂ Jun ₃ H H ch ₃ 4,5-dihydro-5-methylisoxazole- 3-yl 40. ch ₃ SO ₃ CH ₃ H H ch ₃ 4,5-dihydro-5,5- dimethylisoxazol-3-yl 41. CHj $ o _z ch ₃ H H ch ₃ 4,5-Dihydro-5-ethylisoxazole-3- yi 42. ch ₃ Sat ₂ ch ₃ H H ch ₃ 4,5-dihydro-5,5-ethylisoxazole- 3-yl 43. CH _a SO ₂ CH ₃ H H CH ₃ 4,5-dihydroisoxazol-3-yl 44. CH ₃ SO ₂ CH ₃ H H ch ₃ 4,5-dihydro-4,5- dimethylisoxazol-3-yl

Particularly preferred are 4- [2-chloro-3- (4,5-dihydroisoxazol-3-ylH-methylsulfonylbenzoyl) -1-methyl-5-hydroxy-1H-pyrazole, 4- [2-methyl-3- (4,5-Dihydroisoxazol-35-yl) -4-methylsulfonyl-benzoyl] -1-methyl-5-hydroxy-1H-pyrazole, 4- [2-chloro-3- (3-methylisoxazol-5-yl) ~ 4 —Methylsulfonylbenzoyl] -1-methyl-5-hydroxy-1H-pyrazole, 4- [2-chloro-3- (3-methyl-isoxazol-5-yl) -4-methylsulfonylbenzoyl] -1-methyl 1-5-hydroxy-1H-pyrazole and / or their environmentally acceptable salts.

Suitable environmentally acceptable salts are, for example, alkali metal, alkaline earth metal salts, ammonium salts or amines. Suitable adjuvants b) include mixtures of the following:

i) C ₁ -C ₅ -alkyl-C ₅ -C ₂₂ -alkanoáty, with ii) a Cio-C ₂ o-carboxylic acid, iii) a partial phosphoric esters and partial sulfuric esters monohydroxy functional polyalkyl ether and iv) optionally alkylpolyoxyalkylenpolyethery .

Such adjuvants are described, for example, in US 4,834,908, EP 356 812 and EP 553 074.

Suitable C ₁ -C ₅ -alkyl-C ₅ -C ₂₂ -alkanoates (i) are alkyl esters of carboxylic acids wherein the carboxylic acid contains 5 to 22 carbon atoms and the alkanol used for esterification contains 1 to 5 carbon atoms, such as methyl oleate, palmitate, myristate, linolenate, laurate, stearate, pelargonate, ethyl oleate, palmitate, myristate, linolenate, linoleate, laurate, stearate, pelargonate, n-propyl oleate, palmitate, myristate, linolenate, linoleate, laurate, stearate, pelargonate, isopropyl palmitate, myristate, linolenate, linoleate, laurate, stearate, pelargonate, n-butyl oleate, palmitate, myristate, linolenate, laurate, stearate, pelargonate, isobutyl, oleate, palmitate, myristate, linolenate, linoleate, laurate, stearate, pelarate -pentyl oleate, palmitate, myristate, linolenate, linoleate, laurate, stearate, pelargonate.

Methyl oleate, methyl palmitate, ethyl oleate and mixtures thereof are preferred. Preferred C ₁₀ -C ₂₀ o-carboxylic acids (ii) include saturated and mono- and polyunsaturated carboxylic acids such as oleic acid, palmitic acid, myristic acid, linoleic acid, linolenic acid, lauric acid and stearic acid. Oleic acid is preferred.

Particular phosphoric acid esters and sulfuric acid partial esters of monohydroxyfunctional polyalkylene ethers (iii) are those whose polyalkylene ether residues can be prepared by oxalkylating long chain alcohols such as C 10 -C 16 -alkanols, preferably C 10 -C ₁₆ alkanols, with alkylene oxides such as is ethylene oxide, propylene oxide or butylene oxide. Alkylene oxides

They can be used as a mixture or butylene oxide. The alkylene oxides can be used as a mixture or also sequentially for the preparation of block copolymers.

Preferred are polyalkylene ethers having C 10 -C 16 _6- alkyl chain with 10 to 15 moles of ethylene oxide units and 1 to 10, preferably 2 to 6 moles of propylene oxide units.

Preferred products are Klearfac ™ AA 270 from BASF Corporation and Lutensit® A-EP from BASF Aktiengesellschaft io If appropriate, alkyl polyoxyalkylene polyethers can be used simultaneously. Suitable alkyl polyoxyalkylene polyethers are those which can be prepared by oxalkylating C 10 -C ₂₅ -alkanols with alkylene oxides such as ethylene oxide, propylene oxide or butylene oxide.

Preferred are alkyl polyoxyalkylene polyethers having a C 10 -C ₂₅ -alkyl chain, preferably

C | _{A 2} -C ₂₀ -al keel chain, with EO / PO block copolymers such as

Antarox ® BO, Rhodia Emulsogen ® V 2436, Clariant Plurafac ® LF, BASF AG

Dehypon LS, Henkel Dehypon LT, Henkel Synperionic FL, ICI Specialty Chemicals,

Particularly preferred are Plurafac® LF 700, BASF AG.

Adjuvants (b) contain their constituents in the following concentrations:

90% _{Cl-C5-alkyl C5-C22} -alkanoátu, 2-40% Cio-C ₂₀ -carboxylic acid, up to 40% of the partial phosphoric ester or partial sulfuric ester mono3o of hydroxy-functional polyalkyl ethers and up to 75% alkylpolyoxyalkylene polyether.

Preferred concentrations are:

5 to 60% of a C 1 -C ₅ -alkyl-C ₅ -C ₂₂ -alkanoate, 2 to 40% of a C ₁₀ -C ₂₀ o-carboxylic acid, up to 35% of a partial phosphoric acid ester or a partial sulfuric acid ester of a monohydroxy-functional polyalkyl ether; up to 70% of alkyl polyoxyalkylene polyether.

Especially preferred are:

up to 40% of C1-C6 _- alkyl- _C6- C22-alkanoate, 2 to 35% of C1-C12-alkanoate; ₀ -C ₂₀ -carboxylic acids, up to 30% of a partial phosphoric ester or a partial sulfuric acid ester of a monohydroxy-functional polyalkyl ether, and

0 to 70% alkyl polyoxyalkylene polyether.

The herbicidal mixtures of the present invention comprise components a) and b) in the following amounts:

0.5 to 90 wt. A 3-heterocyclyl-substituted benzoyl derivative a);

% to 99.5 wt. adjuvant b).

-4GB 301651 B6

Preferred ratios are:

% to 80 wt. A 3-heterocyclyl-substituted benzoylated derivative a);

20 to 99 wt. adjuvant b).

Here, the components together add 100 wt.

The individual components a) and b) of the herbicidal mixture according to the present invention can be mixed and packaged together or individually.

For agricultural use, the herbicidal mixtures or their individual components are used in a spray tank.

For this purpose, the herbicidal mixture is diluted with water, whereupon further auxiliaries or additives are added. However, the farmer can himself mix the individual components a) and b) of the herbicidal mixture according to the present invention in the spray tank and add, if necessary, other auxiliaries and additives (tank mixing method). In the spray tank mixing method, components a) and b) are mixed in the spray tank and diluted to the desired concentration using water.

Additional excipients and additives may be added for increased processability. The following ingredients have been found to be useful as excipients and additives:

Solvents, anti-foaming agents, buffers, thickeners, spreading agents, compatibility agents.

Examples and types of adjuvants and excipients and additives are described in Farm Chemicals Handbook 1997; Meister Publishing 1997 page CIO "Adjuvant" or 1998 Weed Control Manual page 86.

The composition of the present invention is suitable as a herbicide. The herbicidal mixture acts very efficiently on vegetation outside the crop plants, especially at high application levels. The mixture acts against broadleaf weeds and weed grasses in crop plants such as wheat, rice, corn, soybean and cotton without causing significant damage to the crop plants. This effect is mainly observed at low doses.

Depending on the application method used, the herbicidal mixture may be applied to other useful plants to eliminate undesirable plants. Examples of suitable crops are as follows:

Album cepa, Pineapple comosus, Arachis hypogaea, Asparagus officinalis, Beta vulgaris spec.

altissima, Beta vulgaris spec. rapa, Brassica napus var. napus, Brassíca napus var. napobrassica, Brassica rapa var. New Year's Eve, Camelba sinensis, Carthamus tinctorius, Carya illinoinensis, Citrus limon, Citrus sinensis, Coffea arabica (Coffea canephora, Coffea liberica), Cucumis sativus, Cynodon dactylon arboreum (Gossypium herbaceum, Gossypium vitifobum), Helianthus annuus, Hevea brasiliensis, Hordeum vulgare, Humulus lupulus, Ipomoea batatas, Juglans regia, Lens culinaris, Linnaeus usitatissimum, Lycopersicon lycopersicum, Musus spec. Nicotiana tabacum (N. rustica), Olea europeae, Oryza sativa, Phaseolus lunatus, Phaseolus vulgaris, Picea abies, Pinus spec., Pisum sativum, Prunus avium, Prunus persica, Pyrus communis , Solanum tuberosum, Sorghum bicolor (s. Vulgare), Theobroma cacao, Trifolium pratense, Triticum aestivum, Triticum durum, Vicia faba, Vitis vinifera and Zea mays.

In addition, the herbicidal composition can also be used in useful plants that are resistant to the action of herbicides due to breeding, including genetic engineering methods.

-5GB 301651 B6

The herbicidal mixture may be applied before or after germination. If the herbicidal mixture is less well tolerated by certain crop plants, application methods can be used in which the herbicidal mixture is sprayed using a spraying device in such a way as to come into contact with the leaves of the sensitive crop plants to a minimum or not at all. the leaves of undesirable plants growing under them or not applied to the soil surface.

The herbicidal mixture can be used, for example, in the form of ready-to-use aqueous solutions, powders and suspensions, or also in the form of highly concentrated aqueous, oily or other suspensions or dispersions, emulsions, oil dispersions, pastes, powders, spreading materials or granules to be applied. by spraying, spraying, spraying or pouring. The forms used depend on the intended use; in any case, they are intended to ensure the finest possible dispersion of the herbicidal composition of the present invention.

Suitable inert additives are basically: medium to high boiling mineral oil fractions such as kerosene and diesel, coal tar oils and vegetable or animal oils, aliphatic, cyclic aromatic hydrocarbons such as paraffin, tetrahydronaphthalene, alkylated naphthalenes and derivatives thereof, alkylated benzenes and derivatives thereof, alcohols such as methanol, ethanol, propanol, butanol and cyclohexanol, ketones such as cyclohexanone, strongly polar solvents such as amines such as N-methylpyrrolidone, and water.

Aqueous forms suitable for use may be prepared from emulsion concentrates, suspensions, pastes, wettable powders, or water dispersible granules by the addition of water. To prepare emulsions, pastes or oil dispersions, the herbicidal mixtures used as such or dissolved in an oil or solvent may be homogenized in water using wetting agents, tackifiers, dispersing or emulsifying agents. Alternatively, it is possible to prepare concentrates containing the active ingredients, wetting agents, tackifiers, dispersing or emulsifying agents and, if desired, a solvent or oil, thereby obtaining concentrates suitable for dilution with water.

Suitable surfactants are alkali metal salts, alkaline earth metal salts and ammonium salts of aromatic sulfonic acids, for example ligno-, phenol-, naphthalene- and dibutylnaphthalenesulfonic acid, and fatty acids, alkyl- and alkylarylsulfonates, alkylsulfates, lauryl ether sulfates and fatty alcohol sulfates and salts of sulfated hexa-hepta- and octadecanols, as well as fatty alcohol glycol ethers, condensates of sulfonated naphthalene and its derivatives with formaldehyde, condensates of naphthalene or naphthalenesulionic acids with phenol and formaldehyde polyoxyethylenoctylphenol ether, ethoxylated isooctyl-polyglycolyl, or 1 -polyether alcohols, isotridecyl alcohol, fatty condensates alcohol / ethylene oxide, ethoxylated castor oil, polyoxyethylene-alkyl ethers or poly-propylene-alkyl-ethers, lauryl lal l-poly glycol ether acetate, sorbitol esters, lignin sulphite waste days of water or methylcellulose.

Powders, dispersing materials and powders may be prepared by mixing or grinding the herbicidal mixture together with a solid carrier.

Granules, for example coated granules, impregnated granules and homogeneous granules, can be prepared by binding the herbicidal mixture to solid carriers. Solid carriers are mineral soils such as silicates, silica gels, silicates, talc, kaolin, limestone, lime, chalk, bark, loess, clay, dolomite, diatomaceous earth, calcium sulfate, magnesium sulfate, magnesium oxide, ground synthetic minerals, fertilizers such as ammonium sulfate, ammonium phosphate, ammonium nitrate, ureas and products of plant origin such as flour, ground tree bark, wood flour and ground nut shells, cellulose powders or other solid carriers. The concentrations of the herbicidal compositions in ready-to-use preparations can vary within wide limits. Generally, such formulations comprise from about 0.001 to 98% by weight, preferably 0.01 to 95% by weight, of the herbicidal mixture.

The adjuvant mixture b) can be prepared, for example, as shown in Table 2:

-6GB 301651 B6

Table 2

Component / Mixture no. No. 2 e No. 4 No. 5 No. 6 C-65 Methyl ester ¹¹ 37 30 10 35 5 37 Klearfac * AA 270 ²² 7 15 Dec 15 Dec 2 7/5 22nd Lutensite * A-EP * ¹ 25 Oleic acid 5 35 5 5 Plurafac 'LF 700 ³ ' 75 37.5 Silicone antifoam emulsion ⁵¹ 0.5 0.5 Solvesso * 150 ⁶ ' 51 20 May 34.5 50 35.5

1) 1: 1 Methyl oleate / methyl palmitate (Witco)

2) Ethoxylate / propoxylate fatty acid phosphate (BASF Corporation)

3) Ethoxylate / propoxylate fatty acid alcohol (BASF AG)

4) Ethoxylate / propoxylate fatty acid phosphate (BASF AG)

5) Silicone SKE Wacker i 6) Alkylated aromatic hydrocarbons (Exxon)

To broaden the spectrum of action and to achieve synergistic effects, the herbicidal mixture may be mixed with a variety of representatives of other classes of compounds having a herbicidal or plant growth effect and then applied concurrently. Suitable further components of the mixtures are, for example, 1,2,4-thiadiazoles, 1,3,4-thiadiazoles, amides, aminophosphoric acid and its derivatives, aminotriazoles, anilides, (het) aryloxyalkanoic acids and their derivatives, benzoic acid and its derivatives, benzothiadiazinones , 2-aroy-1,3-cyclohexanediones, heteroaryl arylketones, benzylisoxazolidinones, meta-CF ₃ -phenyl derivatives, carbamates, quinolinecarboxylic acid and its derivatives, dihydrobenzofurans, dihydrofuran-3-ones, dinitroanilines, dinitrophenols, diphenylsters, diphenylsters, diphenylsters, diphenylsters, halocarboxylic acids and their derivatives, ureas, 3-phenyluracils, imidazoles, imidazolinones, N-phenyl-3,4,5,6-tetrahydrophthalimides, oxadiazoles, oxiranes, phenols, aryloxy or heteroaryloxyphenoxypropionic acid esters, phenylacetic acid and its derivatives, phenylpropionic acid and its derivatives derivatives, pyrazoles, phenylpyrazoles, pyridazines, pyridinecarboxylic acid and its derivatives, pyrimidyl ethers, sulfonylureas, triazines, triazinone γ, triazolinones, triazolecarbox25 amides and uracil.

In addition, it may be advantageous to apply the herbicidal mixture, either alone or in combination with other herbicides, in the form of a mixture with other crop protection agents, for example with agents against harmful insects or phytopathogenic fungi or bacteria. Also of interest is the miscibility with mineral salt solutions which are used to overcome the lack of nutrients and trace elements.

Depending on the purpose of use, the season, the target plant and its growth stage, the application rate of the herbicidal mixture is from 0.01 to 1.0, preferably from 0.01 to 0.5, kg of active ingredient per hectare, based on the herbicidal active ingredients. mixtures.

-7EN 301651 B6

DETAILED DESCRIPTION OF THE INVENTION

The herbicidal action of the compositions of the present invention can be documented by the following greenhouse experiments:

The culture vessels that were used were plastic pots containing clay-sandy soil with approximately 3.0% humus as substrate. The seeds of the test plants were sown separately for each species.

io

For pre-germination treatment, the herbicidal mixture, which was suspended or emulsified in water, was applied directly after sowing by means of fine spray nozzles. The containers were gently irrigated to promote germination and growth and subsequently covered with translucent plastic containers until the plants were rooted. These coatings guaranteed uniform germination of the test plants until they were adversely affected by the herbicidal mixture.

For germination treatment, the test plants were first allowed to grow to a height of 3-15 cm depending on the habitat of the plant and then treated with a herbicidal mixture that was suspended or emulsified in water. To this end, the test plants were sown directly and grown in the same pots or were first grown separately as seedlings and then transferred to the test pots a few days before treatment.

Depending on the species, the plants were maintained at a temperature of 10-25 ° C or 20-35 ° C. The testing time was 2 to 4 weeks during which time the plants were treated and their response to the individual treatments was determined.

Evaluation is carried out using a scale of 0 to 100. 100 means that the plant does not germinate at all or that at least a part of it has been completely destroyed above the soil surface and 0 is zero damage or normal growth.

The plants used for greenhouse experiments were the following species:

Abbreviation Latin name ABUTH Abutilon theophrasti SETVI Setaria viridis SET FA Setaria faberi

Example 1

-8EN 301651 B6

Example 2

Table 3

Herbicidal effect after germination in the greenhouse Phytotoxicity Effective AWM SETFA SETVI compound kg per ha / ha Ex. 1 0.05 91.5 75 Ex. 1 0.05 95 95 + + 6, Table 2 0.6 Ex. 1 0.05 85 95 + 4- AG 6202 0.5 + + Ensol 28 5.0

Table 4

Herbicidal effect after germination in the greenhouse Phytotoxicity Effective AWM SETFA SETVI ABUTH compound kg per ha / ha Ex. 2 0.05 57.5 80 92.5 Ex. 2 0.05 97.5 95 100 ALIGN! + + 6, Table 2 0.6 Ex. 2 0.05 82.5 77.5 96.5 + + Lutensol ON 80 0.5 + + Ensol 28 0.56 Ex. 2 0.05 67.5 90 94 + + AG 6202 0.5 + + ammonium sulfate 5.0 Ex. 2 0.05 80 92.5 100 ALIGN! + Ί- Atplus 5, 5 + + Ensol 28 0.56

Legend for adjuvants used:

Name

AG® 62% 2 Akzo alkyl glycoside APG Lutensol® ON 80 BASF AG alkyl ethoxylate Lutensol® ON 110 BASFAG alkyl ethoxylate ENSOL®28 BASF AG ammonium nitrate / urea solution (28% of total N) Atplus Unígema 83% paraffin oil + 17% nonionic emulsifier

-10GB 301651 B6

The data of Tables 3 and 4 clearly show the synergistic effect of the herbicidal two-component mixture of the present invention as compared to the corresponding ternary mixtures and the pure active compound.

Claims (6)

PATENT CLAIMS A herbicidal mixture comprising a) 0.5 to 90 wt. A 3-heterocyclyl-substituted benzoyl derivative of the Formula I wherein: R ¹ is chloro, methyl; 20 R ² is methylsulfonyl; R ³ is hydrogen; X is 4,5-dihydroisoxazolyl; R ⁴ is a pyrazole bonded at the 4-position of formula II to R «OH in which R ⁵ is hydrogen; 30 R @ ⁶ is methyl; or an environmentally acceptable salt thereof; b) 10 to 99.5 wt. an adjuvant, including i) a C 1 -C ₅ -alkyl carboxylic acid ester containing 5 to 22 carbon atoms, ii) a C 10 -C 20 -carboxylic acid, iii) a partial phosphorous ester or a partial sulfur ester of a monohydrofunctional polyalkyl ether, iv) optionally an alkyl polyoxyalkylene polyether In a synergistically effective amount. The herbicidal mixture of claim 1, comprising 4- [2-chloro-3- (4,5-dihydroisoxazol-3-yl) -4-methylsulfonylbenzoyl] -1-methyl-5-hydroxy-1H-pyrazole. A herbicidal mixture as claimed in claim 1, comprising 4- [2-methyl-3- (4,5-diisoxazol-3-yl) -4-methylsulfonylbenzoyl] -1-methyl-5-hydroxy-1H-pyrazole. . Process for preparing a herbicidal mixture according to any one of claims 1 to 3, characterized in that the components a) and b) of the herbicidal mixture are mixed. A method for controlling undesirable vegetation, characterized in that the herbicidally effective amount of components a) and b) of the herbicidal mixture according to any one of claims 1 to 3 is treated separately or simultaneously on the plants or their habitat A method for controlling undesirable vegetation, comprising mixing herbicidally effective amounts of components a) and b) of the herbicidal mixture according to any one of claims 1 to 3 and allowing the mixture to act on the plants or their habitat.